Durable Icephobic Coating for Stainless Steel

In this work, we present a modification of a stainless steel surface to impart superhydrophobic properties to it that are robust with respect to mechanical stresses associated with cyclic icing/deicing treatment, as well as to long-term contact with aqueous media and high humidity. The durability of the superhydrophobic state is ensured by the texture with multimodal roughness stable against mechanical stresses and a 2D polymer network of fluorooxysilane chemically bound to the texture elements. The designed superhydrophobic coating is characterized by contact angles exceeding 155° and a maximum rolling angle of 42° after 100 icing/deicing cycles

Laser Tailoring the Surface Chemistry and Morphology for Wear, Scale and Corrosion Resistant Superhydrophobic Coatings

A strategy, combining laser chemical modification with laser texturing, followed by chemisorption of the fluorinated hydrophobic agent was used to fabricate the series of superhydrophobic coatings on an aluminum alloy with varied chemical compositions and parameters of texture. It was shown that high content of aluminum oxynitride and aluminum oxide formed in the surface layer upon laser treatment allows solving the problem of enhancement of superhydrophobic coating resistance to abrasive loads. Besides, the multimodal structure of highly porous surface layer leads to self-healing ability of fabricated coatings. Long-term behavior of designed coatings in “hard” hot water with an essential content of calcium carbonate demonstrated high antiscaling resistance with self-cleaning potential against solid deposits onto the superhydrophobic surfaces. Study of corrosion protection properties and the behavior of coatings at long-term contact with 0.5 M NaCl solution indicated extremely high chemical stability and remarkable anticorrosion properties

Reinforced Superhydrophobic Coating on Silicone Rubber for Longstanding Anti-Icing Performance in Severe Conditions

We present a simple method for fabricating the superhydrophobic coatings on composite silicone rubber used for electrical outdoor applications. The coating is characterized by contact angles as high as 170° and is mechanically durable in contact with the aqueous phase. We discuss the impact of mechanical durability of the surface texture on the anti-icing performance of the coating on the basis of the experimental data on freezing delay of sessile aqueous droplets. A set of complementary data obtained in laboratory and outdoor experiments on freezing delay time, variation of wettability and practical work of adhesion for supercooled aqueous sessile droplets, impacting behavior of droplets at low negative temperatures, as well as the results of snow and ice accumulation in outdoor experiments indicate the very prospective icephobic properties of the developed coating

Combination of Functional Nanoengineering and Nanosecond Laser Texturing for Design of Superhydrophobic Aluminum Alloy with Exceptional Mechanical and Chemical Properties

Industrial application of metallic materials is hindered by several shortcomings, such as proneness to corrosion, erosion under abrasive loads, damage due to poor cold resistance, or weak resistance to thermal shock stresses, <i>etc</i>. In this study, using the aluminum-magnesium alloy as an example of widely spread metallic materials, we show that a combination of functional nanoengineering and nanosecond laser texturing with the appropriate treatment regimes can be successfully used to transform a metal into a superhydrophobic material with exceptional mechanical and chemical properties. It is demonstrated that laser chemical processing of the surface may be simultaneously used to impart multimodal roughness and to modify the composition and physicochemical properties of a thick surface layer of the substrate itself. Such integration of topographical and physicochemical modification leads to specific surface nanostructures such as nanocavities filled with hydrophobic agent and hard oxynitride nanoinclusions. The combination of superhydrophobic state, nano- and micro features of the hierarchical surface, and the appropriate composition of the surface textured layer allowed us to provide the surface with the outstanding level of resistance of superhydrophobic coatings to external chemical and mechanical impacts. In particular, experimental data presented in this study indicate high resistance of the fabricated coatings to pitting corrosion, superheated water vapor, sand abrasive wear, and rapid temperature cycling from liquid nitrogen to room temperatures, without notable degradation of superhydrophobic performance

Effective Antibacterial Nanotextured Surfaces Based on Extreme Wettability and Bacteriophage Seeding

A method based on nanosecond laser treatment was used to design superhydrophobic and superhydrophilic aluminum alloy substrates showing enhanced cytotoxic activity with respect to <i>Escherichia coli</i> K12 C600 strain. It was shown that the survival of cells adhered to the superhydrophobic substrates was significantly affected by the presence of organic contaminants, which are ubiquitous in hospital practice and the food industry. The peculiarities of the texture also played a notable role in antibactericidal activity. It was found that the superhydrophilic surfaces had much higher toxicity than the superhydrophobic ones, which was explained by the mechanisms of adhesion of cells to the surface. Scanning electron microscopy and tomographic reconstruction of the adhered cells were used to study the variation of cell morphology after attachment to surfaces with different wettability. It was shown that the cytotoxicity of superhydrophobic surfaces could be significantly enhanced by using the combined antimicrobial action of bacteriophages and the superhydrophobicity of the objects